Safety razor blade



Sept. 15, 1931. P. H. UNSINGER 1,823,339

SAFETY RAZOR BLADE Filed April 15. 1930 IN VEN TOR.

A TTORNE Y.

Patented Sept. 15, 1931 q I UNITED STATES PATENT OFFICE PHILIP H. UNSINGER, OF MAPLEWOOD, NEW JERSEY SAFETY RAZOR BLADE Application filed April 15, 1830. Serial No. 444,380.

This invention relates to improvements in to abnormal jars, such as result from dropsafety razor blades, and, more particularly, ping. to safety razor blades of the double edge Having the above matters in mind, it is the object ofthis invention to provide a novel ty e. Vhen using ordinary double edge safety construction of safety razor'blade having razor blades, the same are mounted in a holdmeans to prevent fractures, if occurring, from er comprising a guard base and a removable running or carrying back through the body clamp head or cap, so as to be clamped beof the blade; and, furthermore, to provide a tween said parts which are of curvilinear form of stud receiving perforation which,

10 shape in cross-section so as to flex the blade while so engaging the studs of the holder as about its longitudinal axis. When the blades to securely retain the blade against longiare thus clamped and flexed, it is not of intudinal and lateral play in the holder, will frequent occurrence that the blade fractures at the same time reduce the tension of the so as to break off portions or all of the cutblade body along a median longitudinal line,

ting edge. Fractures sometimes occur by thus tending to permit said blade'body to reason of a too tight pressure of the clamp easily flex at such median line with less tenhead or cap, and sometimes the fractures redency to set up undue or unequal strainsor sult from dropping the holder and blade stresses in the outlying longitudinal half whereby the corners of the holder base or sections thereof, whereby all tendency to 30 clamp head or both are bent from proper fracture under blows or jars is greatly replane, so that when the blade is clamped and duced. v flexed therebetween unequal stress is exerted An illustrative embodiment of a double on the corner sections of the blade, Which edge safety razor blade according to this intend to start a fracture'at such corner. Such Vention is shown in the drawings, in which fractures, however caused, usually start at FI 1 is a large face view of the novel blade an end of the blade body inward of a cutting of this invention; Fig. 2 is a face view of an edge, and either run throughout the length ordinary double edge safety razor blade as of the blade body so as to separate the entire heretofore commonly used, said view showadjacent cutting edge therefrom, or the fracmg a characteristic result of fracture; and

tures run diagonally to a point along the Flg. is a face view of the blade according f cutting edge so as to separate a substantial to this inveinion, showing the manner in portion of the cutting edge portion from the which a fracture, if occurring, is prevented blade body. In either event the cutting edge from running back through the blade body,

ortion thus separated is quite likely to be and is confined to a limited and small corner 35 displaced relative to the guard members of portion of the blade. 7'. the base, so as to work out beyond the same, Similar characters of reference are emwith risk of producing a dangerous gash in ployed in the above described views, to indithe face of the user, should the fractured catc corresponding parts. condition of the blade not have been discov- Referring to the drawings, the reference ered before shaving. Another factor contribcharacter '5 indicates the blade body, which is 73 uting to possible fracture of ordinary double made Offhlll tempered steel. The op osite edge safety razor blades, is that, owing to the longitudinal margins of said blade bo y are stiffness and temper of the blade body along ground and honed to provide the usual cutits longitudinal axis, which is not materially ting edges 6 along each side thereof. H reduced by the longitudinally spaced seplrov1ded in each corner of the blade body arate perforations provided to engage the 5, inwardly of the ad acent cutting edge and studs of the holder, resistance to flexure is near the end margin of the blade, are perforsuch that-strains are set up which tend to renations 7. Preferably these perforations 7 are der the blades more easily subject to the ocof triangular shape,hav1ng their bases 7'sub- H currences of fracture, especially if subjected stantially parallel to the longitudinal axis of the blade body, and their inner "sides 7 more or less parallel to the blade ends. It will be understood, however, that said erforations may be otherwise shaped, the pre erred shape described being selected for the reason that it produces a weakened neck 8 at the blade cutting edges which, should fracture occur, will readily break through at such predetermined point, said predetermined point being so located as to lie under a guard tooth of the holder so as not to expose a corner likely to produce scratches on further use of the blade. In Fig. 2 .there is shown a double edge blade a of well known common form in which the effect of fracture is illustrated. Usually the break b starts at an end of the blade and runs inwardly through the body thereof, sometimes throughout the entire leng-.h of the same, but most often in a diagonal line eventually intersecting the adjacent cutting edge. As a result of the break a substantial section a of the blade body and a cutting edge thereof is entirely separated therefrom. Such section 0 will either become displaced from the holder so as to present a portion of the cutting edge out of alignment with the holder guardmembers, with resultant risk of gashing the face of-the user, should the break not be discovered before using the razor; or, if the broken section dro s out of the holder leave but an unexposed b ade portion.

In the novel blade made according to this invention, owing to the provision of the described perforations 7, if, when'the same is clamped and flexed in the holder, a fracture begins at the end of the blade, the same, in starting to run longitudinally inward through the blade body, will encounter almost at once the adjacent perforation 7 into which it will extend, with the result that it is blocked thereby from penetrating further into the said body, and thus checked without injury to the adjacent blade edge; or, if the stress to which the fracture is due is great enough, the break will be diverted when the perforation is encountered and caused to extend through the blade edge at a. predetermined point, thus merely removing a limited corner area of the blade with minimum reduction of the cutting edge, whereby the latter is substantially preserved for continued use, even after such corner portion is removed. The latter efl'ect is illustrated in Fig. 3 of the drawings, which shows but asmall corner section d of the blade body removed.

Referring again to Fig. 1 of the drawings, in addition to the novel features already adverted to, a novel form of continuous stud receiving perforation 9 is shown, which continues uninterruptedly throughout the blade body so as to terminate short of the blade ends, whereby two longitudinal blade sections are provided connected by easily flexed median portions 10. Said perforation 9 is vided in its margins, whereby the blade holder studs may not only extend through the blade body, but will be so engaged by said abutments 11 as to adequately hold the blade against both longitudinal and lateral displacement. Owing to the continuous formation of perforation, a substantial amount of metal is removed along the longitudinal center of the blade leaving only the median portions 10 at each end thereof to connect the blade sections and to maintain the integrity of the blade body as a whole, with the result that the tension of the blade body along its longitudinal axis is reduced, so that the blade sections may be more readily flexed and, when flexed, reducing the stresses and strains which contribute to the likely occurrence of fractures, as above referred to. From the above description it will be obviousthat the present invention provides a novel form and construction of double edge safety razor blade, wherein tendency to the occurrence of fractures is greatly reduced, and wherein, should frac.ures occur, the same are controlled and directed so as to effect substantially no material injury to the cutting edges of the blade.

Having thus described the present invention, I claim s 1. A safety razor blade, comprising a body of thin flexible steel having cutting edges along the opposite longitudinal margins thereof, said body having an uninterrupted central perforation extending along the longitudinal median line thereof, the margins of said central perforation being formed to provide diagonally and oppositely exposed holder stud engaging abutments, said central perforation being adapted to form median portions at the ends of the blade body between the longitudinal sections thereof whereby resistance to flexure of the blade is reduced, said body having additional fracture diverting perforations inward of the cutting edges thereof and respectively adjacent to the blade ends.

2. A safety razor blade, comprising a body of thin flexible steel having cutting edges along the opposite longitudinal margins thereof, said body having an uninterrupted central perforation extending along the longitudinal median line thereof, the margins of said central perforation being formed to provide diagonally and opposltely exposed holder stud engaging abutments, said central perforation being adapted to form median portions at the ends of the blade body between the longitudinal sections thereof whereby resistance to flexure of the blade is reduced, said body having additional fracture diverting perforations of substantially triangular shape located inward of the cutting edges therof and respectively adjacent 13 to the blade ends, said perforations having their bases substantially arallel to the longitudinal axis of said bla e body, their inner sides substantially parallel to the ends of said blade body, and their apexes directed mud an adjacent cutting edge of said blade 3. A safety razor blade, comprising a body of flexible steel having cutting edges along opposite longitudinal margins thereof, said 'body havin fracture diverting perforations of substantlally triangular shape located inward of the cutting ed es thereof and respectively adjacent to the lade ends.

4. A. safety razor blade, comprising a body of flexible steel having cutting edges alon opposite longitudinal margins thereof, sai body having fracture diverting perforations of substantially triangular shape located inward of the cutting edges thereof and respectively adjacent to the blade ends, and said perforations having their bases substantially parallel to the longitudinal axis of said blade body, their inner, sides substantially. parallel to the ends of said blade body, and

their. a exes directed toward an adjacent cut- I ting e ge of said blade body.

In testimon that I claim the invention set forth above PHI 11 H. UNSINGER.

have hereunto set my hand this 14th day of A 

